Ring gap theory

[enkeivette]

Total seal recommends a 22 first, 14 second ring gap. I've been getting recommendations from engine builders to run a 26 first and a 24 second. :o

So before I file off an extra 10/1000ths I want to think it through. To me it seems that a ring gap is there for expansion, and without extra space to expand the ring may bind and tend to break.

The theory behind more gap on the second is that it will somehow help the first ring seal better. I don't see how that would help. If the gap is theoretically gone at max heat, the ring is acting like a solid ring with the purpose of creating a 'total seal' (haha). So why would you need a vent on the second ring? Seems to me that the second ring is there to help the seal fighting blowby past the first ring. And if it only needs 14/1000ths gap to prevent bind, then running more would only allow more blowby with no advantage.

Unless yall convince me, I think I'm going to run 22/14.

[BRUTAL64]

Total seal recommends a 22 first, 14 second ring gap. I've been getting recommendations from engine builders to run a 26 first and a 24 second. :o

So before I file off an extra 10/1000ths I want to think it through. To me it seems that a ring gap is there for expansion, and without extra space to expand the ring may bind and tend to break.

The theory behind more gap on the second is that it will somehow help the first ring seal better. I don't see how that would help. If the gap is theoretically gone at max heat, the ring is acting like a solid ring with the purpose of creating a 'total seal' (haha). So why would you need a vent on the second ring? Seems to me that the second ring is there to help the seal fighting blowby past the first ring. And if it only needs 14/1000ths gap to prevent bind, then running more would only allow more blowby with no advantage.

Unless yall convince me, I think I'm going to run 22/14.

Ok, here goes..... I run a top ring gap of .028 --why you ask-- it has to with piston temp. Hyper pistons run at a higher temp then regular cast or forged.

So look at ring gap as a temp thing. The more temp the piston runs at the wider the gap has to be. A few thousands is not going to cause you a blow by problem. Remember you have a second ring-that also acts as an oil scraper.

If the ring gap is TOO narrow, as it heats up it will butt ends, bind in the bore and RIP the top of the piston off.

Your call.:drink:

[enkeivette]

Sooo many SBCs and sooo many different answers on everything! You'd think it would be a science by now.

And what about the 2nd ring? 14 or 24?!

[enkeivette]

Called Total Seal again, this time he recommended a 24/20... :sm_laughing:

[BRUTAL64]

Sooo many SBCs and sooo many different answers on everything! You'd think it would be a science by now.

And what about the 2nd ring? 14 or 24?!

Listen to Uncle Glenn. Neither.

Take what the manufacture tells you (you did tell them it was forced induction) and add a couple of thousands.

The more temp the pistons retain the WIDER the gap has to be.

This is not a Science and not even an ART it is a best guess.:bang:


The more boost the higher the piston temp.:drink:


The wider the better on a new combo that is untried.

What was the gap on the old rings?

[BRUTAL64]

Called Total Seal again, this time he recommended a 24/20... :sm_laughing:

There you go. Sounds good to me. Go with that.


You do know I'm building a new engine?? So you better get it right. I'd hate to see you beat by a NA motor.:laugh:

[enkeivette]

There you go. Sounds good to me. Go with that.


You do know I'm building a new engine?? So you better get it right. I'd hate to see you beat by a NA motor.:laugh:

If you made 400hp on $11.25 I want to see 800hp this time on not more than $22.50. :bigthumbsup:

[BRUTAL64]

If you made 400hp on $11.25 I want to see 800hp this time on not more than $22.50. :bigthumbsup:

Actually that was $12.00. That extra 75 cents got me another 50 hp.:rolling:

The 377 should come out to about 530 hp and around 480 ftlbs.
The 404 0r 406 should be around 550 hp and 540 ftlbs.

I figure to have around $3000 in it with new heads and crank/pistons.

Either 400 motor will have a red line of about 7,200 rpm.
The 377 is a new build for me, so RPM I figure will be about 7,600.

Doesn't mean I'll spin them that far:p. The $12.00 motor went to 7,000 rpm all the time. :judge:

The 496 (if I do it) would be around 650 hp and 600 ftlbs.:nutkick:

[enkeivette]

You forgot to subtract 25% hp and add 25 % cost for real world factors. And another 15% hp till you dyno tune it. :D

5 out of 8 pistons done now.

One more ques for yall, or just Glenn :sm_laughing: The 1st and 2nd ring gaps are 180 out, does it matter if the oil rings are 180 out? And is that accordian lookin oil control ring at all directional? I've just been thumbing the oil rings on without much thought or care.

Tension ring on the bottom with the indent facing downwards next to the pin, oil ring above it, then the accordian ring, then another oil ring. No real orientation or clocking.

First ring (24) chamfer up, 2nd ring (20) chamfer down and dot up.

[BRUTAL64]

You forgot to subtract 25% hp and add 25 % cost for real world factors. And another 15% hp till you dyno tune it. :D

5 out of 8 pistons done now.

One more ques for yall, or just Glenn :sm_laughing: The 1st and 2nd ring gaps are 180 out, does it matter if the oil rings are 180 out? And is that accordian lookin oil control ring at all directional? I've just been thumbing the oil rings on without much thought or care.

Tension ring on the bottom with the indent facing downwards next to the pin, oil ring above it, then the accordian ring, then another oil ring. No real orientation or clocking.

First ring (24) chamfer up, 2nd ring (20) chamfer down and dot up.

Biggest thing is to not line up the gaps:sm_laughing:

Oil ring- the top and bottom thin ring gap should be at least 30 degrees from the expander (large center) gap. You could do the 180 degree thing here also but it is more important to make sure the expander gap is supported completely by the upper and lower rings.:drink:

[94cobra69ss396]

I also prefer to have the 1st and 2nd ring gaps on the sides of the piston over the pin. Not sure it matters but I just don't like the thought of having the gap on the ends that see the most wear.

[BRUTAL64]

I also prefer to have the 1st and 2nd ring gaps on the sides of the piston over the pin. Not sure it matters but I just don't like the thought of having the gap on the ends that see the most wear.

I did it that way on this current engine following your way of thinking. I didn't really see any difference in any thing doing it this way as opposed to the usual Chevy way.

I always followed Chevy's procedures on ring placement until this motor. I knew this motor was only for a short time.:drink:

[big_G]

I believe that ring placement is over-blown (no pun intended). They move around the groove all the time. Just don't set them in lined up.